Oracle 参数 INMEMORY_MAX_POPULATE_SERVERS 官方解释，作用，如何配置最优化建议
本站中文解释
INMEMORY_MAX_POPULATE_SERVERS参数指定用于填充In-Memory Column Store的进程数量。 该参数不得超过PARALLEL_MAX_SERVERS参数的值(默认为16)，可以设置的值介于1-128之间，如果设置为0(默认值)，那么系统使用与并行操作有关的参数来确定进程数量，通常情况下单个默认库的进程数量和系统的资源有关。
要设置INMEMORY_MAX_POPULATE_SERVERS参数，需要使用ALTER system命令，该命令使用下面的格式：
ALTER SYSTEM SET INMEMORY_MAX_POPULATE_SERVERS = VALUE;
其中VALUE是开发者想要设置的值，通常情况下，VALUE设置为8-16之间的数值。
官方英文解释
INMEMORY_MAX_POPULATE_SERVERS specifies the maximum number of background populate servers to use for In-Memory Column Store (IM column store) population, so that these servers do not overload the rest of the system.
| Property | Description |
|---|---|
|
Parameter type |
Integer |
|
Default value |
Half of the value of See the “CPU_COUNT” description for information about how |
|
Modifiable |
|
|
Modifiable in a PDB |
No |
|
Range of values |
0 to a value based on the number of cores in the system. |
|
Basic |
No |
|
Oracle RAC |
All instances should use the same value. |
This parameter has meaning only if the INMEMORY_SIZE parameter is also set to a positive value.
The value to use for this parameter depends on the number of cores in the system. A certain percentage of CPU should be allocated for in-memory background population, and this parameter should be set accordingly. You can also set this parameter to 0 to temporarily disable populate tasks on the system from executing.
Note:
Be careful not to set the value of this parameter too high. If it is set close to the number of cores or higher, no CPU could be left for the rest of the system to run.
Note:
The IM column store is not populated if this parameter is set to 0.
See Also:
-
“INMEMORY_CLAUSE_DEFAULT”
-
“INMEMORY_FORCE”
-
“INMEMORY_QUERY”
-
“INMEMORY_SIZE”
-
Oracle Database In-Memory
Guide for an introduction to the IM column store -
Oracle Database In-Memory
Guide for more information about the IM column store
